
n = input("请输入：")
end = len(n)-1
start = 0
flag = True
while start<end:
    if n[start]!=n[end]:
        flag = False
        break
    start = start + 1
    end = end - 1
if flag:
    print(n, "是回文数")
else:
    print(n, "不是回文数")
